Does anyone bump your bullets

[dtknowles]

It seems that some bench rest shooters bump their bullets. How is it done?

I hit some bore riding bullets on the nose with a hammer.

270085

270086

they seem to make uniform contact with the bore with an equal mark from each land.

Tim

[ndnchf]

See my post #6 in this thread.
http://castboolits.gunloads.com/showthread.php?410731-simple-swaging

[Tripplebeards]

I do in my marlin 336 in 35 Rem. You can see the results in my avatar. My barrel slugs at .357 and I size at .3595 so my boolit is large enough that the rifling engraves about 1/2 the length of my boolit when chamberd.

[dtknowles]

I do in my marlin 336 in 35 Rem. You can see the results in my avatar. My barrel slugs at .357 and I size at .3595 so my boolit is large enough that the rifling engraves about 1/2 the length of my boolit when chamberd.

Is it a bore riding bullet or are you just jamming the bearing surface into the lands? You aren't bumping them up only sizing them down. My barrel slugs 0.308 and I size them to 0.310. I don't know how to measure my bore diameter but I am guessing that it is around 0.300 and the nose of my bullet is 0.298.

Tim

[dtknowles]

See my post #6 in this thread.
http://castboolits.gunloads.com/showthread.php?410731-simple-swaging

Cool but I don't have an arbor press and I don't think I want to use my drill press. I already broke the handle on a lubrisizer trying to swage beyond its capability.

Actually what you are doing is an inspiration. I could use sizer die and a modified bolt with a nut to set the length and just whack the bolt with my hammer. I actually want to do the hammer thing as it just upsets the nose and not the whole bullet. I think if you press them slow the whole bullet gets swaged but if you bump/whack them only the nose of the bullet is affected. In the picture I think if you look close with your eyes crossed you can see that not even the whole nose is bumped up just the front half. Without something to control the process I am worried I will get inconsistent results. Thanks for the inspiration.

Tim

[Tripplebeards]

Here is a photo of my boolit after chambering...

https://i.imgur.com/EbbV7xG.jpg

[ndnchf]

Tim - do you have a sturdy vise? That would probably work instead of the arbor press.

[charlie b]

Bump first, then size (in case you had not figured that out yet :) ).

Hammer is very inconsistent. This is an area you want to be the same each time. For my bore riders the nose section is long enough that I use a nose size die from NOE. Not all bores are the same. Savage .308 bore is .302, grooves .309.

To bump up I'd use a die in the press with a stop collar. That way you get the same 'crush' each time. Like you said, a die with a screw adjustment should work best. The stop collar can be as simple as a stack of washers.

[country gent]

I know of some BPCR shooters who swage up to size after casting. Nose and body. They claim running thru the same die gives an exact bullet form and also any voids are compressed to minimize them. These dies are made to very exact specks and final lap to the actual bullet. It then is installed in a heavy press and the bullets squeezed to the final form. There is a mechanical ejector set up. no hammers. Some dies even have a small squirt hole to bleed lead off in a small amount to maintain an exact weight. Basically swaging the bullet from the casting.

[dtknowles]

I know of some BPCR shooters who swage up to size after casting. Nose and body. They claim running thru the same die gives an exact bullet form and also any voids are compressed to minimize them. These dies are made to very exact specks and final lap to the actual bullet. It then is installed in a heavy press and the bullets squeezed to the final form. There is a mechanical ejector set up. no hammers. Some dies even have a small squirt hole to bleed lead off in a small amount to maintain an exact weight. Basically swaging the bullet from the casting.

Doesn't that mess up the lube grooves and gas check seat?

Tim

[dtknowles]

Tim - do you have a sturdy vise? That would probably work instead of the arbor press.

Yes, and it might not be that slow. I am thinking I only need a tiny amount to squish.

Tim

[dtknowles]

Bump first, then size (in case you had not figured that out yet :) ).

Hammer is very inconsistent. This is an area you want to be the same each time. For my bore riders the nose section is long enough that I use a nose size die from NOE. Not all bores are the same. Savage .308 bore is .302, grooves .309.

To bump up I'd use a die in the press with a stop collar. That way you get the same 'crush' each time. Like you said, a die with a screw adjustment should work best. The stop collar can be as simple as a stack of washers.

I sized before and after but the way I did it the sizing after did not seem to matter. The body of the bullet did not expand. Regarding the consistency of using a hammer, that is all about the operator. If you drop the hammer from the same height each time you will get the same impact impulse.

Tim

[country gent]

Lube in the grooves protects the grooves, and very few gcs on these bullets. I may make a die for PP bullets to swage up and true the nose. I could also put the full radius on the nose pour moulds noses.

[waksupi]

My Swede prefers a bumped bullet. I use the lubrisizer, set the throw to give me the bump I need, and run them through. I generally do it separately from lubing, but can't see any reason to not do it in one operation.

[RU shooter]

I've squished some bullets for my 32 spl that were a touch small on the nose for my barrel I just used a flat nose seater stem in my 38 spl die and adjusted it to squish just the right amount to bump the nose up the right amount shot as well as any other bullets

[1bluehorse]

I just use a large bolt that matches the press threads and thread it into the press, place a flat piece of metal on top of the ram, set the bullet on that and use the press's leverage. That's after lubing the bullet.

[rbuck351]

I use an old Swag-o-Matic to swag boolits up to what ever size I need. It swags the whole boolit to what ever shape and size you can make dies for. I start with a sized lubed boolit and the lube grooves remain.

[dtknowles]

My bullets are linotype. Not as easy to swage.

Tim

[beagle]

If all you're interested in is nose fit, and dependent on your alloy hardness, you might be able to get by with bumping in a sizer if all you're interested in is the nose. Back off pressure on the lube. Run the bullet down as far as the diving bands. Put pressure with the top punch on the nose of the bullet and give it about 1/16" "crunch" and see what you get. Should give you the amount you need.
Doesn't take much pressure. I bump HP cavities with a home made top punch to give me 1/8" diameter HP cavities in .380 bullets.
But, don't get too carried away./beagle

[NuJudge]

I bump .32 HBWC bullets in a swage die, the Speers come at about .313", and I need about .3145". There are various commercial makers who make presses and dies.